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Three Pieces of Information
| Feature | What It Tells You |
|---|---|
| Number of peaks | Number of different hydrogen environments |
| Integration (area) | Ratio of H atoms in each environment |
| Splitting pattern | Number of H atoms on adjacent carbons (n+1 rule) |
The n+1 Splitting Rule
A signal is split into (n+1) peaks, where n = number of H atoms on neighbouring carbons.
| n (neighbours) | Pattern | Name |
|---|---|---|
| 0 | 1 peak | Singlet (s) |
| 1 | 2 peaks | Doublet (d) |
| 2 | 3 peaks | Triplet (t) |
| 3 | 4 peaks | Quartet (q) |
Chemical Shift Ranges (δ / ppm)
| Environment | δ / ppm |
|---|---|
| R–CH₃ (alkyl) | 0.9–1.0 |
| R–CH₂–R | 1.2–1.4 |
| R–O–CH (near O) | 3.3–4.3 |
| R–CHO (aldehyde) | 9.4–10.0 |
| R–COOH (acid) | 10.0–12.0 |
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